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If the dissociation constant of [Cu(NH₃)₄]²⁺ is X × 10¹². Determine X.

Cu2+ + NH3 ⇌ [Cu(NH3)]2+ K1 = 104 [Cu(NH3)]2+ + NH3 ⇌ [Cu(NH3)]2+ K2 = 1.58 × 103 [Cu(NH3)2]2+ + NH3 ⇌ [Cu(NH3)3]2+ K3 = 5 × 102 [Cu(NH3)3]2+ +... View Article

For a chemical reaction, K_eq is 100 at 300K, the value of ΔG^o is –xR Joule at 1 atm pressure. Find the value of x. (Use ln 10 = 2.3)

Answer: 1382 Given: Keq= 100 at 300K and ΔGo = –xR Joule ΔGo = -RTln(Keq) = -2.303RTlog(Keq) = -1381.8R Therefore, x = 1381.8 or 1382... View Article

Calculate the time taken in seconds for 40% completion of a first order reaction, if its rate constant is 3.3× 10^-4sec^-1.

Answer: 1518 = 30 x 103 x 0.506 = 1518 sec... View Article

S₈ + bOH^– → cS^2- + sS₂O^2-₃ + H₂O. Find the value of c.

Answer: 4 Let us look at the half reactions i.e. oxidation and reduction separately. Oxidation: S8 → S2O2-3 S8 + 24OH- → 4S2O2-3 + 12H2O... View Article

For the given reaction at equilibrium, moles of Cl₂(g) is equal to the moles of Cl(g) and the equilibrium pressure is 1atm. If K_p of this reaction is x ×10^–1, find x.

Cl2(g) ⇌ 2Cl(g) Answer: 5 According to the question: Cl2 ⇌ 2Cl [Ptotal = 1 atm]. Moles of Cl2 = Moles of Cl (at equilibrium). Given: Kp = x... View Article

Arrange Mg, Al, Si, P and S in the correct order of their ionisation potentials.

Answer: P > S > Si > Mg > Al In the third period of the periodic table, Element Valence Shell Configuration Na... View Article

The composition of gun metal is:

a. Cu, Zn, Sn b. Al, Mg, Mn, Cu c. Cu, Ni, Fe d. Cu, Sn, Fe Answer: (a) The components of gun metal are: Copper ~ 88% Tin ~ 8% Zinc ~ 4%... View Article

The slope of the straight line given in the following diagram for adsorption is:

a. 1/n (0 to 1) b. 1/n (0.1 to 0.5) c. log n d. log (1/n) Answer: (a) According to Freundlich adsorption isotherm, log (x/m) = log K + 1/n... View Article

Identify X, Y, Z in the given reaction sequence.

a. X = Na[Al(OH)4] ; Y = CO2 ; Z = Al2O3.xH2O b. X = Na[Al(OH)4] ; Y = SO2 ; Z = Al2O3.xH2O c. X = Al(OH)3 ; Y = CO2 ; Z = Al2O3 d. X =... View Article

E^o_M²⁺_{/ M} has a positive value for which of the following elements of 3d transition series?

a. Cu b. Zn c. Cr d. Co Answer: (a) According to the electrochemical series, elements present above H have positive Eo value. For M2+(aq)/... View Article

In the given reactions,

1) I2 + H2O2 + 2OH- → 2I- + 2H2O + O2 2) H2O2 + HOCl → Cl- + H3O+ + O2 a. H2O2 acts as an oxidising agent in both the reactions b. H2O2 acts as... View Article

S-1: Colourless cupric metaborate is converted into cuprous metaborate in a luminous flame.

a. S-1 is true and S-2 is false b. S-1 is false and S-2 is true c. Both are false d. Both are true Answer: (c) Cupric metaborate (Cu(BO2)2... View Article

Which of the following ores are concentrated by cyanide of group 1^st element?

a. Sphalerite b. Malachite c. Calamine d. Siderite Answer: (a) Cyanide acts as a depressant and is therefore used to concentrate the... View Article

Which of the following pairs are isostructural

a) TiCl4, SiCl4 b) SO2-3, CrO2-3 c) NH3, NO-3 d) ClF3, BCl3 a. A, B b. A, C c. B, C d. A, D Answer: (a) Isostructural compounds... View Article

Find A and B.

Answer: (c)... View Article

Which reagent (A) is used for the following given conversion?

a. Cu / ∆ / high pressure b. Molybdenum Oxide c. Manganese Acetate d. Potassium Permanganate Answer: (b) Molybdenum Oxide acts as a... View Article

The products A and B are:

Answer: (a) Alkenes reacting with cold, dilute KMnO4 will give 1,2-diols (vicinal diols). This is called syn- dihydroxylation. CrO3 cannot... View Article

Identify the major product:

Answer: (b)... View Article

Global Cybersecurity – India in Top 10: RSTV – Big Picture

Rajya Sabha TV programs and discussions are very insightful and informative from a UPSC perspective. In this article, we provide a gist of the... View Article

What is the major product of the following reaction?

Answer: (c) Since HI is an acid, the pi bond attacks H+ and a carbocation intermediate is formed. Since this is a secondary carbocation,... View Article

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